1 / 23

Colorado Flood-A fe w images and thoughts

Colorado Flood-A fe w images and thoughts. Richard Grumm NWS State College PA 16803. Where it rained-black dot is Boulder Stage-IV data; NMQ Q2 and CCPA was used not shown here . When it rained. Timing is EVERYTHING.

fleta
Download Presentation

Colorado Flood-A fe w images and thoughts

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Colorado Flood-A few images and thoughts Richard Grumm NWS State College PA 16803

  2. Where it rained-black dot is BoulderStage-IV data; NMQ Q2 and CCPA was used not shown here

  3. When it rained

  4. Timing is EVERYTHING

  5. Why it rained strong ridge weak front easterly flow into terrain convectively favorable environment

  6. Deep moisture PW +4sHow would this look in PDF not s

  7. Easterly flow into the terrain +4s

  8. Pattern of heavy rainfallPontrelli et al 1999: a) Madison County 1995, b) Fort Collins 1997, c) Rapid City 1972 and d) Big Thompson Canyon 1977

  9. Fronts and winds same 4 Cases

  10. Idealized pattern for orographic record rainfall Pre-standardize anomaly era

  11. Predictable? EC Forecasts QPF

  12. EC Patternall models were quite similar

  13. EC PW patternsimilar to SREF/GFS/NAM

  14. EC Windshmm…SREF is next….

  15. SREF WindsLarger anomalies Batman

  16. GFS QPFwhat is a record event in this time frame in the GFS M-CLIMATE?

  17. SREF Probability of 150 mmBoulder is a red dot…..

  18. Prob 100 mm

  19. Mean QPF and 50mm contours by member

  20. SummaryPatterns and Probabilities • Pattern known to be associated with upslope and similar to many heavy rain events involving terrain • Well research and good examples of historic events from the past. • Pattern well predicted by any system we looked at. • Standardized anomalies may have provide clue about high PW and strong easterly flow • Good pattern with good anomaly signature • Trevor could likely provide PDF of the PW and u-winds in affected region • QPF: • variable in spatial and temporal distribution • Many uncertainty issues along with clues to the rainfall potential • EC in key time was not a silver bullet (EC-lite) • We need internal model climatology M-Climate so EFI like products alert use to near record or record QPF in every forecast system verse it’s internal a climate • Link: http://cms.met.psu.edu/sref/severe/2013/12Sep2013.pdf

  21. Future things to consider in 0-8 hours • Rainfall verse NOAA-14 data for alerts • Forecasts of Rainfall verse NOAA-14 for alerts • Russ Schumacher sites and examples here • Flash Flood guidance and NOAA-14 data for alerts and heads up at critical thresholds. • Better storm scale ensembles

  22. Stage-IV verse NOAA-14 return periods

  23. 13 Sept

More Related